Electrostriction and guidance of acoustic phonons in optical fibers
Résumé
We investigate the generation of acoustic phonons in optical fibers via electrostriction from coherent optical waves. Solving the elastodynamic equation subject to the electrostrictive force, we are able to reproduce the experimental spectra found in standard and photonic crystal fibers. We discuss the two important practical cases of forward interaction, dominated by elastic resonances of the fiber, and backward interaction, for which an efficient mechanism of phonon guidance is found. The last result describes the formation of the coherent phonon beam involved in stimulated Brillouin scattering.